Conventionally, the amount consumed for electricity, tap water, or gas is measured by manually reading the meters settled in each accommodation including houses or buildings by meter-readers, converted into the corresponding rates to be charged in a respective office, and billed to each individual house or building.
It is general that meter-readings for such amount displayed on the meters are conducted by meter-readers, who visit each place of the meter and writes it down on a check board after read it by a sight. Therefore, the conventional method for meter-reading works has several problems such that it needs many human resources, and has an inefficiency as well as an inaccuracy due to manual records.